CN103627972B - ZG25MnSY3 casting material and preparation method thereof - Google Patents
ZG25MnSY3 casting material and preparation method thereof Download PDFInfo
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- CN103627972B CN103627972B CN201310552288.9A CN201310552288A CN103627972B CN 103627972 B CN103627972 B CN 103627972B CN 201310552288 A CN201310552288 A CN 201310552288A CN 103627972 B CN103627972 B CN 103627972B
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Abstract
The invention discloses a ZG25MnSY3 casting material which consists of the following components in percentage by mass: 0.25-0.3 percent of C, 0.3-0.45 percent of Si, 1-1.2 percent of Mn, less than or equal to 0.02 percent of P, less than or equal to 0.015 percent of S, 0.3-0.6 percent of Cr, 04-0.6 percent of Ni, 0.3-0.45 percent of Mo, 0.09-0.15 percent of V, less than or equal to 0.05 percent of Nb, less than or equal to 0.3 percent of Cu, 0.03-0.06 percent of Al and the balance of Fe, totaling 100 percent. The invention also discloses a preparation method of a casting by utilizing the ZG25MnSY3 casting material. The casting material is smelted in an electric-arc furnace and a refining furnace, a leavening agent is added into the casting material at the later refining stage, the casting material has a good metallographic structure, the mechanical property is greatly improved, the strength and toughness are improved, and the service life is prolonged.
Description
Technical field
The invention belongs to cast material technical field, relate to a kind of ZG25MnSY3 casting material, the invention still further relates to and utilize this kind of ZG25MnSY3 material to prepare the method for foundry goods.
Background technology
Along with the development of foundry engieering, more and more higher to the performance requriements of foundry goods, this just requires that foundry goods will have good material, good metallographic structure and higher mechanical property, and guarantee foundry goods is wear-resisting, antifatigue in use, ensures that foundry goods does not in use deform, ruptures.Especially, in the colliery of underground coal mining, the safety of security to operator's life of foundry goods, the continuity work of equipment operation, all serve vital effect.
Summary of the invention
The object of this invention is to provide a kind of ZG25MnSY3 casting material, solve existing foundry goods in use wear-resisting, fatigue performance is not enough, the problem in use easily deform, ruptured.
Another object of the present invention is to provide and a kind ofly utilizes this kind of ZG25MnSY3 material to prepare the method for foundry goods.
The technical solution adopted in the present invention is, a kind of ZG25MnSY3 casting material, is made up of according to quality % following component:
C is 0.25%-0.3%, Si be 0.3%-0.45%, Mn is 1% ~ 1.2%, P is≤0.02%, S be≤0.015%, Cr is 0.3%-0.6%, Ni is 0.4%-0.6%, Mo is 0.3%-0.45%, V be 0.09% ~ 0.15%, Nb is≤0.05%, Cu is≤0.3%, Al is 0.03%-0.06%, and all the other are Fe, adds up to 100%.
Another technical scheme of the present invention is, a kind of method utilizing above-mentioned ZG25MnSY3 material to prepare foundry goods, specifically implements according to following steps:
Step 1, EBT electric furnace is utilized to carry out just practicing
1.1) Composition Control, should meet C≤0.15%, P≤0.005% during electric furnace steel tapping;
1.2) high-quality steel scrap, the stub bar of impurity few, low P, S is selected
First tank material allocate that lime is Metal Weight into 4 ~ 5%; In time a large amount of slagging oxidation period and add slag charge, P≤0.005% when guaranteeing to tap;
1.3) steel remaining slag operation is stayed in employing, stays steel amount 5 ~ 7t, forbids oxidation sludge to enter refining bag;
1.4) first furnace tapping temperature: 1650 ~ 1680 DEG C, uses strong reductor for 0.5Kg/t steel during pre-deoxidation operation.
Step 2, LF refining furnace is utilized to carry out refining
2.1) refining bag is hung after on buggy ladle carry out argon replaces as early as possible;
The set-up procedure of refining bag is:
2.1.1) check each position of refining bag, confirm that each position is normal;
2.1.2) refining bag must be cleaned out, cylinder-packing without steel scrap, without dry slag, slag line mend that area is not more than slag line area by replacing a damaged part 50%;
Install slide gate nozzle, confirming mechanism is in good working state;
2.1.3) check residual height and the ventilation property of gas permeable brick, guarantee residual high safety, ventilative good; Refining bag must toast good before using;
2.2), after refining bag being sent to refining station, thermometric, slag charge is added,
Slag charge consists of: lime and quality of fluorite, than being 4-5:1, control at 200 ± 10mm after refinery scum;
2.3) diffusion deoxidizer selects C powder, ferrosilicon powder, silicon calcium powder and aluminium powder, diffusion deoxidizer will add in batches, treat that slag bleaches, viscosity is suitable, after thermometric sampling, according to analytical results, liquid steel temperature is raised to >=1620 DEG C after adjust alloying constituent, after alloying, temperature is raised to 1590 ± 10 DEG C, get total analysis sample and gas sample, treat that composition is suitable and reach [O]≤30ppm, [N]≤70ppm, [H]≤3.0ppm with gas ingredients;
2.4) to pressure-fired be kept in refining later stage LF refining furnace, continue to add diffusion deoxidizer, keep reducing atmosphere;
2.5) refining time is not less than 45 minutes, require after above-mentioned alloy compositions adds refining white slag hold-time >=20 minutes, add ferro-vanadium before tapping;
2.6) refining furnace tapping temperature is 1580 ± 10 DEG C;
Step 3, to pour into a mould
Cast requires cryogenic fast injection, and teeming temperature is 1545 ± 10 DEG C, and simultaneously press foundary methods drawing moulding complete for foundry goods, pours into a mould, obtain ZG25MnSY3 foundry goods after casting parts thermal insulation, shake out, finishing by pouring technology temperature;
Step 4, positive tempering is carried out to ZG25MnSY3 foundry goods.
The invention has the beneficial effects as follows, by contrasting existing casting material, by reducing and increase some alloying element, through electric arc furnace and refining furnace melting and add alterant in the refining later stage, ensure foundry goods Chemical Composition, by reasonable, suitable thermal treatment process, make foundry goods obtain good metallographic structure, and foundry goods mechanical property is significantly improved, improve intensity and the toughness of foundry goods, reduce foundry goods parts replacement frequency, extend foundry goods work-ing life.
Embodiment
Below in conjunction with embodiment, the present invention is described in detail.
ZG25MnSY3 casting material of the present invention, is made up of according to quality % following component:
C is 0.25%-0.3%, Si be 0.3%-0.45%, Mn is 1% ~ 1.2%, P is≤0.02%, S be≤0.015%, Cr is 0.3%-0.6%, Ni is 0.4%-0.6%, Mo is 0.3%-0.45%, V be 0.09% ~ 0.15%, Nb is≤0.05%, Cu is≤0.3%, Al is 0.03%-0.06%, and all the other are Fe, adds up to 100%.
With reference to table 1, be that the organization design of ZG25MnSY3 casting material of the present invention requires performance index.
Table 1, ZG25MnSY3 casting material organization design of the present invention requires performance index
Other technical indicator of ZG25MnSY3 casting material of the present invention also comprises:
1）O≤50ppm、H≤10ppm、N≤150ppm；
2) annealed structure is that perlite adds ferrite, grain fineness number more than 8 grades;
3) Full Annealing (normalizing+high tempering) after casting, is organized as a small amount of granular bainite+perlite+ferrite, grain fineness number more than 9 grades.
The present invention utilizes above-mentioned ZG25MnSY3 material to prepare the method for foundry goods, comprise electric furnace just to refine → LF refining → cast → thermal treatment process, each component is added successively in smelting process, carries out final chemical composition mass percent and controls, specifically implement according to following steps:
Step 1, EBT electric furnace is utilized to carry out just practicing
1.1) Composition Control (element mass content %): during in order to ensure LF refining, chemical composition is qualified, should meet C≤0.15%, P≤0.005% during electric furnace steel tapping;
1.2) the high-quality steel scrap of impurity few, low P, S, stub bar (getting Fe and P wherein, S) is selected
The melting down remnants of guaranteeing meet processing requirement, the first tank material allocate that lime is Metal Weight into 4 ~ 5%; In time a large amount of slagging oxidation period and add slag charge, P≤0.005% when guaranteeing to tap;
1.3) steel remaining slag operation is stayed in employing, stays steel amount 5 ~ 7t, forbids oxidation sludge to enter refining bag;
1.4) first furnace tapping temperature: 1650 ~ 1680 DEG C, uses strong reductor (such as Al) for 0.5Kg/t steel during pre-deoxidation operation.
Step 2, LF refining furnace is utilized to carry out refining
2.1) refining bag is hung after on buggy ladle carry out argon replaces as early as possible;
The set-up procedure of refining bag is:
2.1.1) check each position of refining bag, confirm that each position is normal;
2.1.2) refining bag must be cleaned out, cylinder-packing without steel scrap, without dry slag, slag line mend that area is not more than slag line area by replacing a damaged part 50%, must not use and newly build bag or the new ladle changing the bag end; Install slide gate nozzle, confirming mechanism is in good working state;
2.1.3) check residual height and the ventilation property of gas permeable brick, guarantee residual high safety, ventilative good; Refining bag must toast good before using;
2.2), after refining bag being sent to refining station, thermometric, slag charge is added,
Slag charge consists of: lime and quality of fluorite, than being 4-5:1, control after refinery scum about 200mm ± 10;
2.3) diffusion deoxidizer selects C powder, ferrosilicon powder, silicon calcium powder and aluminium powder, in order to ensure furnace reduction atmosphere, diffusion deoxidizer will add in batches, treat that slag bleaches, viscosity is suitable, after thermometric sampling, according to analytical results, liquid steel temperature is raised to >=1620 DEG C after adjust alloying constituent, after alloying, temperature is raised to 1590 ± 10 DEG C, gets total analysis sample and gas sample, treat that composition is suitable and reach [O]≤30ppm, [N]≤70ppm, [H]≤3.0ppm with gas ingredients;
2.4) to pressure-fired be kept in refining later stage LF refining furnace, continue to add diffusion deoxidizer, keep reducing atmosphere;
In refining process, will observe argon gas situation the moment, adjustment argon pressure and flow, be advisable with not exposed molten steel face in good time;
2.5) refining time is not less than 45 minutes, require after above-mentioned alloy compositions adds refining white slag hold-time >=20 minutes, add ferro-vanadium before tapping;
2.6) refining furnace tapping temperature is 1580 ± 10 DEG C.
Since then, casting quality composition all meets design requirements, and wherein four embodiment heat (four stove steel) ultimate constituents are with reference to showing 2-1 to showing 2-4;
Table 2-1, the ultimate constituent table (constituent content is quality %) of the embodiment of the present invention 1
| C | Si | Mn | P | S | Cr |
| 0.29 | 0.32 | 1.1 | 0.015 | 0.01 | 0.55 |
| Ni | Mo | V | Nb | Cu | Al |
| 0.56 | 0.38 | 0.095 | 0.045 | 0.25 | 0.034 |
Gaseous constituent is: [O]=26ppm, [N]=54ppm, [H]=3.1ppm.
Table 2-2, the ultimate constituent table (constituent content is quality %) of the embodiment of the present invention 2
| C | Si | Mn | P | S | Cr |
| 0.26 | 0.35 | 1.15 | 0.013 | 0.012 | 0.5 |
| Ni | Mo | V | Nb | Cu | Al |
| 0.44 | 0.33 | 0.1 | 0.03 | 0.3 | 0.04 |
Gaseous constituent is: [O]=20ppm, [N]=60ppm, [H]=4ppm.
Table 2-3, the ultimate constituent table (constituent content is quality %) of the embodiment of the present invention 3
| C | Si | Mn | P | S | Cr |
| 0.28 | 0.41 | 1.18 | 0.010 | 0.005 | 0.4 |
| Ni | Mo | V | Nb | Cu | Al |
| 0.51 | 0.40 | 0.12 | 0.04 | 0.2 | 0.05 |
Gaseous constituent is: [O]=30ppm, [N]=55ppm, [H]=8ppm.
Table 2-4, the ultimate constituent table (constituent content is quality %) of the embodiment of the present invention 4
| C | Si | Mn | P | S | Cr |
| 0.27 | 0.4 | 1.2 | 0.02 | 0.009 | 0.38 |
| Ni | Mo | V | Nb | Cu | Al |
| 0.45 | 0.36 | 0.14 | 0.05 | 0.15 | 0.03 |
Gaseous constituent is: [O]=27ppm, [N]=53ppm, [H]=6ppm.
Step 3, to pour into a mould
Cast requires cryogenic fast injection, and teeming temperature is 1545 ± 10 DEG C, and simultaneously press foundary methods drawing moulding complete for foundry goods, pours into a mould, obtain ZG25MnSY3 foundry goods after casting parts thermal insulation, shake out, finishing by pouring technology temperature.
Step 4, positive tempering is carried out to ZG25MnSY3 foundry goods
Precaution: flame directly must not burn workpiece, adopt blower fan cooling during normalizing, level up during foundry goods shove charge and put surely, shove charge thermal treatment, performs according to technique.
Foundry goods at normalizing process was: 200 ± 10 DEG C of insulations 3 ± 0.1 hours, ensure to heat up again after foundry goods heart portion and hull-skin temperature are evenly, heat-up rate is not easily too high, heat-up rate controls at≤50 DEG C/h(heat-up rate too high, easily causes the stress crack that the distortion of foundry goods and heart portion and surface temperature difference cause too greatly; And heat-up rate is too low, then loses time, waste energy); When foundry goods is warming up to 650 ± 10 DEG C, be incubated 4 ± 0.1 hours further, homogeneous surface and heart portion temperature; Heat up after casting temperature is even, heat-up rate controls at≤60 DEG C/h again; Casting temperature is heated to 920 ± 10 DEG C of insulations 16 ± 0.2 hours, then comes out of the stove and carries out normalizing spraying process (require that when spraying fan operation is good, spraying evenly); Treat that foundry goods is cooled to 150-200 DEG C, be incubated 3 ± 0.1 hours, again enter stove tempering heat treatment, heat-up rate controls at≤60 DEG C/h, and casting temperature is heated to 620 ± 10 DEG C of insulations 20 ± 0.2 hours, to eliminate casting stress and normalizing stress, air cooling to room temperature.
After tempering terminates, four embodiment foundry goods cut attached casting testing material respectively, be processed into standard tension specimen and three impact specimens, by standard through row performance test, through experimental test, final performance is as shown in table 3, meets the design requirements of table 2.
Table 3, embodiment of the present invention ZG25MnSY3 structure property actual measurement index
In sum, ZG25MnSY3 material of the present invention and foundry goods thereof meet design requirements, have excellent mechanical property, have a good application prospect.
Claims (3)
1. a ZG25MnSY3 casting material, its feature is, is made up of according to quality % following component: C is 0.29%, Si is 0.32%, Mn be 1.1%, P is 0.015%, S is 0.01%, Cr be 0.55%, Ni is 0.56%, Mo is 0.38%, V be 0.095%, Nb is 0.045%, Cu is 0.25%, Al is 0.034%, and all the other are Fe, adds up to 100%.
2. a method for foundry goods prepared by ZG25MnSY3 material, and its feature is,
This ZG25MnSY3 casting material, is made up of according to quality % following component: C is 0.25%-0.3%, Si is 0.3%-0.45%, Mn is 1% ~ 1.2%, P be≤0.02%, S is≤0.015%, Cr is 0.3%-0.6%, Ni be 0.4%-0.6%, Mo is 0.3%-0.45%, V is 0.09% ~ 0.15%, Nb be≤0.05%, Cu is≤0.3%, Al is 0.03%-0.06%, all the other are Fe, add up to 100%, specifically implement according to following steps:
Step 1, EBT electric furnace is utilized to carry out just refining
1.1) Composition Control, i.e. element mass content %: during in order to ensure LF refining, chemical composition is qualified, should meet C≤0.15%, P≤0.005% during electric furnace steel tapping;
1.2) high-quality steel scrap, the stub bar of impurity few, low P, S is selected
First tank material allocate that lime is Metal Weight into 4% ~ 5%; In time a large amount of slagging oxidation period and add slag charge, P≤0.005% when guaranteeing to tap;
1.3) steel remaining slag operation is stayed in employing, stays steel amount 5 ~ 7t, forbids oxidation sludge to enter refining bag;
1.4) first furnace tapping temperature: 1650 DEG C ~ 1680 DEG C, uses strong reductor for 0.5Kg/t steel during pre-deoxidation operation;
Step 2, LF refining furnace is utilized to carry out refining
2.1) refining bag is hung after on buggy ladle carry out argon replaces as early as possible;
The set-up procedure of refining bag is:
2.1.1) check each position of refining bag, confirm that each position is normal;
2.1.2) refining bag must be cleaned out, cylinder-packing without steel scrap, without dry slag, slag line mend that area is not more than slag line area by replacing a damaged part 50%;
Install slide gate nozzle, confirming mechanism is in good working state;
2.1.3) check residual height and the ventilation property of gas permeable brick, guarantee residual high safety, ventilative good; Refining bag must toast good before using;
2.2), after refining bag being sent to refining station, thermometric, slag charge is added,
Slag charge consists of: lime and quality of fluorite are than being 4-5:1, and refinery scum is thick to be controlled at 200 ± 10mm;
2.3) diffusion deoxidizer selects C powder, ferrosilicon powder, silicon calcium powder and aluminium powder, diffusion deoxidizer will add in batches, treat that slag bleaches, viscosity is suitable, after thermometric sampling, according to analytical results, liquid steel temperature is raised to >=1620 DEG C after adjust alloying constituent, after alloying, temperature is raised to 1590 ± 10 DEG C, get total analysis sample and gas sample, treat that composition is suitable and reach [O]≤30ppm, [N]≤70ppm, [H]≤3.0ppm with gas ingredients;
2.4) to pressure-fired be kept in refining later stage LF refining furnace, continue to add diffusion deoxidizer, keep reducing atmosphere;
2.5) refining time is not less than 45 minutes, require after above-mentioned alloy compositions adds refining white slag hold-time >=20 minutes, add ferro-vanadium before tapping;
2.6) refining furnace tapping temperature is 1580 ± 10 DEG C;
Step 3, to pour into a mould
Cast requires cryogenic fast injection, and teeming temperature is 1545 ± 10 DEG C, and simultaneously press foundary methods drawing moulding complete for foundry goods, pours into a mould, obtain ZG25MnSY3 foundry goods after casting parts thermal insulation, shake out, finishing by pouring technology temperature;
Step 4, positive tempering is carried out to ZG25MnSY3 foundry goods.
3. the method for foundry goods prepared by ZG25MnSY3 material according to claim 2, and its feature is: described positive tempering process process is:
200 ± 10 DEG C of insulations 3 ± 0.1 hours, heat-up rate controlled at≤50 DEG C/h, when foundry goods is warming up to 650 ± 10 DEG C, is incubated 4 ± 0.1 hours; Heat-up rate controls at≤60 DEG C/h, and casting temperature is heated to 920 ± 10 DEG C of insulations 16 ± 0.2 hours, then comes out of the stove and carries out normalizing spraying process; Treat that foundry goods is cooled to 150-200 DEG C, be incubated 3 ± 0.1 hours, again enter stove tempering heat treatment, heat-up rate controls at≤60 DEG C/h, and casting temperature is heated to 620 ± 10 DEG C of insulations 20 ± 0.2 hours, and air cooling is to room temperature.
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| CN105002438A (en) * | 2015-07-08 | 2015-10-28 | 中冶陕压重工设备有限公司 | SY17MnNiVNbTi steel and preparation method of SY17MnNiVNbTi steel structural member |
| CN108070766A (en) * | 2016-11-15 | 2018-05-25 | 宜兴市乐华冶金辅助材料有限公司 | A kind of wear-resisting alloy cast material |
| CN107058680A (en) * | 2017-03-29 | 2017-08-18 | 河钢股份有限公司承德分公司 | A kind of LF refining deoxidation slagging method for producing the low silicon cold-forging steel of middle carbon |
| CN108048744A (en) * | 2017-12-13 | 2018-05-18 | 梅州市梅县区雄辉实业有限公司 | A kind of high-tenacity wear-resistant steel and preparation method thereof |
| CN110468329B (en) * | 2019-08-15 | 2021-08-03 | 中冶陕压重工设备有限公司 | ZG-SY09MnCrNiMo RE steel and casting preparation method |
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